Method and apparatus for transmitting and receiving system information

ABSTRACT

A communication method and system for converging a fifth generation (5G) communication system for supporting higher data rates beyond a fourth generation (4G) system with a technology for Internet of things (IoT) are provided. The communication method and system may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. A method of a terminal receiving a paging message is provided. In addition, a method of a terminal acquiring system information is provided.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation application of prior application Ser.No. 16/366,331, filed on Mar. 27, 2019, which has issued as U.S. Pat.No. 11,206,633 on Dec. 21, 2021, which was based on and claims priorityunder 35 U.S.C. § 119 (a) of an Indian patent application number201811011728, filed on Mar. 28, 2018, in the Indian Patent Office, thedisclosure of which is incorporated by reference herein in its entirety.

BACKGROUND 1. Field

The disclosure relates to a system and a method of master informationblock (MIB) acquisition in wireless communication system.

2. Description of the Related Art

To meet the demand for wireless data traffic having increased sincedeployment of fourth generation (4G) communication systems, efforts havebeen made to develop an improved fifth generation (5G) or pre-5Gcommunication system. Therefore, the 5G or pre-5G communication systemis also called a ‘beyond 4G network’ or a ‘post long term evolution(LTE) System’. The 5G wireless communication system is considered to beimplemented not only in lower frequency bands but also in higherfrequency (mm Wave) bands, e.g., 10 GHz to 100 GHz bands, so as toaccomplish higher data rates. To mitigate propagation loss of the radiowaves and increase the transmission (TX) distance, the beamforming,massive multiple-input multiple-output (MIMO), full dimensional MIMO(FD-MIMO), array antenna, an analog beam forming, and large scaleantenna techniques are being considered in the design of the 5G wirelesscommunication system. In addition, in 5G communication systems,development for system network improvement is under way based onadvanced small cells, cloud radio access networks (RANs), ultra-densenetworks, device-to-device (D2D) communication, wireless backhaul,moving network, cooperative communication, coordinated multi-points(CoMP), reception-end interference cancellation and the like. In the 5Gsystem, hybrid frequency shift keying (FSK) and quadrature amplitudemodulation (QAM), frequency QAM (FQAM) and sliding window superpositioncoding (SWSC) as an advanced coding modulation (ACM), filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA), and sparse codemultiple access (SCMA) as an advanced access technology have beendeveloped.

The Internet, which is a human centered connectivity network wherehumans generate and consume information, is now evolving to the internetof things (IoT) where distributed entities, such as things, exchange andprocess information without human intervention. The internet ofeverything (IoE), which is a combination of the IoT technology and thebig data processing technology through connection with a cloud server,has emerged. As technology elements, such as “sensing technology,”“wired/wireless communication and network infrastructure,” “serviceinterface technology,” and “Security technology” have been demanded forIoT implementation, a sensor network, a machine-to-machine (M2M)communication, machine type communication (MTC), and so forth have beenrecently researched. Such an internet of things (IoT) environment mayprovide intelligent Internet technology services that create a new valueto human life by collecting and analyzing data generated among connectedthings. IoT may be applied to a variety of fields including smart home,smart building, smart city, smart car or connected cars, smart grid,health care, smart appliances, and advanced medical services throughconvergence and combination between existing information technology (IT)and various industrial applications.

In line with this, various attempts have been made to apply 5Gcommunication systems to IoT networks. For example, technologies, suchas a sensor network, MTC, and M2M communication may be implemented bybeamforming, MIMO, and array antennas. Application of a cloud RAN as theabove-described big data processing technology may also be considered tobe as an example of convergence between the 5G technology and the IoTtechnology.

In the recent years several broadband wireless technologies have beendeveloped to meet the growing number of broadband subscribers and toprovide more and better applications and services. The second generation(2G) wireless communication system has been developed to provide voiceservices while ensuring the mobility of users. Third generation (3G)wireless communication system supports not only the voice service butalso data service. The 4G wireless communication system has beendeveloped to provide high-speed data service. However, the 4G wirelesscommunication system currently suffers from lack of resources to meetthe growing demand for high speed data services. Therefore, the 5Gwireless communication system is being developed to meet the growingdemand of various services with diverse requirements, e.g., high speeddata services, support ultra-reliability and low latency applications.

In addition, the 5G wireless communication system is expected to addressdifferent use cases having quite different requirements in terms of datarate, latency, reliability, mobility etc. However, it is expected thatthe design of the air-interface of the 5G wireless communication systemwould be flexible enough to serve the user equipments (UEs) having quitedifferent capabilities depending on the use case and market segment theUE cater service to the end customer. Example use cases the 5G wirelesscommunication system is expected to address is enhanced mobile broadband(eMBB), massive machine type communication (m-MTC), ultra-reliable lowlatency communication (URLL) etc. The eMBB requirements like tens ofGbps data rate, low latency, high mobility so on and so forth addressthe market segment representing the conventional wireless broadbandsubscribers needing internet connectivity everywhere, all the time andon the go. The m-MTC requirements like very high connection density,infrequent data TX, very long battery life, low mobility address so onand so forth address the market segment representing the IoT/IoEenvisioning connectivity of billions of devices. The URLL requirementslike very low latency, very high reliability and variable mobility so onand so forth address the market segment representing the industrialautomation application, vehicle-to-vehicle/vehicle-to-infrastructurecommunication foreseen as one of the enabler for autonomous cars.

In the 4G wireless communication system, evolved node B (eNB) or basestation (BS) in a cell broadcast system information (SI). SI isstructured into a master information block (MIB) and a set of systeminformation blocks (SIBs). MIB consists of a system frame number (SFN),downlink system bandwidth (BW), and physical hybrid automatic repeatrequest (ARQ) feedback indicator channel (PHICH) configuration. MIB istransmitted every 40 ms. It is repeated every 10 ms wherein the firsttransmission (TX) occurs in subframe #0 when SFN mod 4 equals zero. MIBis transmitted on physical broadcast channel (PBCH). SIB Type 1 (i.e.,SIB 1) carries cell identity, tracking area code, cell barringinformation, value tag (common for all scheduling units), and schedulinginformation of other SIBs. SIB 1 is transmitted every 80 ms in subframe#5 when SFN mod 8 equals zero. SIB 1 is repeated in subframe #5 when SFNmod 2 equals zero. SIB 1 is transmitted on physical downlink sharedchannel (PDSCH). Other SIBs (i.e., SIB 2 to SIB 19) are transmitted inan SI message wherein scheduling information of these SIBs are indicatedin SIB 1.

UE acquires the SI at cell selection, cell reselection, after handovercompletion, after entering evolved universal mobile telecommunicationssystem (UMTS) terrestrial radio access (E-UTRA) from another radioaccess technology (RAT), upon re-entering service area, upon receiving anotification (paging), and upon exceeding the maximum validity duration(3 hour). In radio resource control (RRC) idle state and inactive state,UE needs to acquire MIB, SIB 1, SIB 2 to SIB 5, SIB 6 to SIB 8(depending on RAT supported), SIB 17 (if LTE-wireless local area network(WLAN) interworking (IWK) is supported), and SIB 18 to SIB 19 (if D2D issupported). In an RRC connected state, UE needs to acquire MIB, SIB 1,SIB 2, SIB 8 (depending on RAT supported), SIB 17 (if LTE-WLAN IWK issupported), and SIB 18 to SIB 19 (if D2D is supported).

In the 4G wireless communication system, SI change is notified through apaging message (in RRC_IDLE or RRC_CONNECTED) with causesystemInfoModification to let the UE know that some SI is changing inthe next modification period. UE is not provided with the details ofwhich SI is updated. There are certain drawbacks in this approach ofchange notification. If an SIB is updated in a cell, all the UE's campedto that cell are notified that there is change in SI. Based on thisnotification, UE does not know which SIB is updated. So, UE has todiscard all the acquired SIBs and has to reacquire all of themirrespective of whether UE is interested in the SIB which is updated ornot. This leads to unnecessary power consumption at UE.

In the 5G wireless communication system (also referred as nextgeneration radio or new radio (NR)), SI (i.e., one or more SIBs or SImessages) is transmitted over PDSCH. The carrier BW is also partitionedinto multiple bandwidth parts (BWPs) in frequency domain. The PDSCHcarrying SI is transmitted over the initial downlink (DL) BWP. Theconfiguration of initial DL BWP is signaled in MIB. The MIB istransmitted on a PBCH. The PBCH is transmitted in a synchronizationsignal (SS) block (SSB) together with synchronization signals (i.e.,primary SS (PSS)/secondary SS (SSS)). The SSB spans 4 orthogonalfrequency division multiplex (OFDM) symbols in time domain and 240subcarriers in frequency domain. The subcarrier spacing (SCS) used forSSB is fixed per frequency band. There is a configurable offset betweenstarting resource block (RB) of SSB and starting RB of initial DL BWP.The SCS used for SSB carrying MIB and SCS for other DL channels(physical downlink control channel (PDCCH)/PDSCH used for systeminformation) transmitted in initial DL BWP can also be different.

In the legacy system, whenever UE receives a paging message including SIupdate notification, UE always reacquire the MIB irrespective of whetherMIB is updated or not. In next generation radio, MIB contains severalparameters such as systemFrameNumber (6 bits most significant bit(MSB)), subCarrierSpacingCommon, ssb-SubcarrierOffset,dmrs-TypeA-Position, pdcch-ConfigSIB1, cellBarred andintraFreqReselection information. Once the UE has acquiredsystemFrameNumber in a cell, UE does not need to reacquire MIB again forsystemFrameNumber while staying on the camped cell in IDLE/INACTIVEstate or while being served in CONNECTED state. However, if UE undergoescell re-selection in IDLE/INACTIVE state or handover in CONNECTED stateneeds to reacquire MIB of re-selected/target cell. The parametersssb-SubcarrierOffset, dmrs-TypeA-Position, pdcch-ConfigSIB1, cellBarred,and intraFreqReselection can be updated by network in a cell but theseupdates happen rarely. MIB contents are transmitted on PBCH along withlayer 1 (L1) contents comprising systemFrameNumber (4 bits leastsignificant bit (LSB)), half frame bit and 3 bits for SS/PBCH blockindex (3 MSBs for above 6 GHz operation), otherwise, 1 bit forsubcarrier (SC) offset and 2 bits reserved (for below 6 GHz operation).The total PBCH size including MIB contents, L1 contents and 24 bitscyclic redundancy check (CRC) is 56 bits. Also these parameters (i.e.MIB contents and L1 contents) are not updated whenever one or more SIBsare updated by network. So reacquiring MIB every time one or more SIBsare updated is unnecessary.

In next generation radio, acquisition of MIB (i.e. PBCH decoding) mayrequire UE to switch to BW of SSB from BW of initial DL BWP (where UEreceives remaining minimum system information (RMSI)/on demand SI(OSI)/Paging), as there is a configurable offset between starting RB ofSSB and starting RB of initial DL BWP. Acquisition of MIB may alsorequire SCS switching as SCS used for MIB and SCS for other DL channels(PDCCH/PDSCH used for RMSI/OSI/Paging) can be different. The RRCCONNECTED UE, UE can be configured to monitor and receive DLtransmissions from a next generation node B (gNB) in one or more DLBWPs. DL BWPs in which UE receive in DL is referred as active DL BWP.The acquisition of MIB every time any SI is updated leads to datainterruption for RRC CONNECTED UE as MIB may not be present in UE'sactive DL BWP. The acquisition of MIB every time any SI is updated leadsto data interruption, unnecessary power consumption and delay to acquireto the updated system information.

Therefore, an enhanced method of updating MIB and SI is needed.

The above information is presented as background information only toassist with an understanding of the disclosure. No determination hasbeen made, and no assertion is made, as to whether any of the abovemight be applicable as prior art with regard to the disclosure.

SUMMARY

Aspects of the disclosure are to address at least the above-mentionedproblems and/or disadvantages and to provide at least the advantagesdescribed below. Accordingly, an aspect of the disclosure is to providea communication method and system for converging a fifth generation (5G)communication system for supporting higher data rates beyond a fourthgeneration (4G) system.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

In the legacy system, whenever user equipment (UE) receives a pagingmessage including system information (SI) update notification, UE alwaysreacquires the master information block (MIB) irrespective of whetherMIB is updated or not. In next generation radio or new radio (NR), theparameters (i.e., MIB contents and layer 1 (L1) contents) are notupdated whenever one or more SIBs are updated by network. So reacquiringMIB every time one or more SIBs are updated is unnecessary and leads todata interruption, unnecessary power consumption and delay to acquire tothe updated system information. In next generation radio, acquisition ofMIB (i.e., PBCH decoding) may require UE to switch to bandwidth (BW) ofsynchronization signal (SS) block (SSB) from BW of initial downlink (DL)bandwidth part (BWP) (where UE receives remaining minimum systeminformation (RMSI)/on demand SI (OSI)/paging), as there is aconfigurable offset between starting resource block (RB) of SSB andstarting RB of initial DL BWP. Acquisition of MIB may also requiresubcarrier spacing (SCS) switching as SCS used for MIB and SCS for otherDL channels (physical downlink control channel (PDCCH)/physical downlinkshared channel (PDSCH) used for RMSI/OSI/paging) can be different. Theradio resource control (RRC) CONNECTED UE, UE can be configured tomonitor and receive DL transmissions from next generation node B (gNB)in one or more DL BWPs. DL BWPs in which UE receive in DL is referred asactive DL BWP. The acquisition of MIB every time any system informationis updated leads to data interruption for RRC CONNECTED UE as MIB maynot be present in UE's active DL BWP. The acquisition of MIB every timeany system information is updated leads to data interruption,unnecessary power consumption and delay to acquire to the updated systeminformation. The disclosure overcomes these problems.

In accordance with an aspect of the disclosure, a method of a terminalreceiving a paging message is provided. The method includes determininga paging frame based on an offset, a discontinuous reception (DRX) cycleof the terminal, a number of paging frames in the DRX cycle, and anidentifier of the terminal, wherein information on the offset isobtained from system information, determining a paging occasion based ona number of paging occasions for the paging frame, the paging occasionincluding a set of physical downlink control channel (PDCCH) monitoringoccasions, and monitoring the paging occasion to receive the pagingmessage.

In accordance with another aspect of the disclosure, a terminalreceiving a paging message is provided. The terminal includes atransceiver configured to receive signals from a base station (BS) andtransmit signals to the base station, and a controller coupled with thetransceiver and configured to determine a paging frame based on anoffset, a discontinuous reception (DRX) cycle of the terminal, a numberof paging frames in the DRX cycle, and a identifier of the terminal,wherein information on the offset is obtained from system information,determine a paging occasion based on a number of paging occasions forthe paging frame, the paging occasion including a set of PDCCHmonitoring occasions, and monitor the paging occasion to receive thepaging message.

In accordance with another aspect of the disclosure, a method of aterminal acquiring system information is provided. The method includesreceiving an indication about change of system information, and acquirea system information block 1 (SIB 1) based on a state of the terminal.

In accordance with another aspect of the disclosure, a terminalacquiring system information is provided. The terminal includes atransceiver configured to receive signals from a base station (BS) andtransmit signals to the base station, and a controller coupled with thetransceiver and configured to control the transceiver to receive anindication about change of system information, and acquire a systeminformation block 1 (SIB 1) based on a state of the terminal.

Other aspects, advantages, and salient features of the disclosure willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses various embodiments of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the disclosure will be more apparent from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 shows the user equipment (UE) operations based on Embodiment 1according to Method 1 of the disclosure;

FIG. 2 shows signaling between a UE and a next generation node B (gNB)wherein a notification is included in a paging message based onEmbodiment 1 according to Method 1 of the disclosure;

FIG. 3 shows signaling between a UE and a gNB wherein a notification isincluded in paging downlink control information (DCI) based onEmbodiment 1 according to Method 1 of the disclosure;

FIG. 4 shows UE operations based on Embodiment 2 according to Method 1of the disclosure;

FIG. 5 shows UE operations for a master information block (MIB) andsystem information (SI) update based on Embodiment 3 according to Method1 of the disclosure;

FIG. 6 shows signaling between a UE and a next generation node B (gNB)based on Embodiment 3 according to Method 1 of the disclosure;

FIG. 7 shows UE operations for a master information block (MIB) andsystem information (SI) update based on Embodiment 3 according to Method1 of the disclosure;

FIG. 8 illustrates next generation node B (gNB) operations in oneembodiment according to Method 2 of the disclosure;

FIG. 9 illustrates next generation node B (gNB) operations in oneembodiment according to Method 3 of the disclosure;

FIG. 10 illustrates next generation node B (gNB) operations in oneembodiment according to Method 3 of the disclosure;

FIG. 11 illustrates next generation node B (gNB) operations in oneembodiment according to Method 3 of the disclosure;

FIG. 12 illustrates next generation node B (gNB) operations in oneembodiment according to Method 3 of the disclosure;

FIG. 13 illustrates next generation node B (gNB) operations in oneembodiment according to Method 3 of the disclosure;

FIG. 14 shows three patterns for transmitting remaining minimum systeminformation (RMSI) in a fifth generation (5G) wireless communicationsystem;

FIG. 15 is a block diagram of a terminal according to an embodiment ofthe disclosure; and

FIG. 16 is a block diagram of a base station (BS) according to anembodiment of the disclosure.

Throughout the drawings, like reference numerals will be understood torefer to like parts, components, and structures.

DETAILED DESCRIPTION

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of variousembodiments of the disclosure as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the various embodiments describedherein can be made without departing from the scope and spirit of thedisclosure. In addition, descriptions of well-known functions andconstructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of thedisclosure. Accordingly, it should be apparent to those skilled in theart that the following description of various embodiments of thedisclosure is provided for illustration purpose only and not for thepurpose of limiting the disclosure as defined by the appended claims andtheir equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

By the term “substantially” it is meant that the recited characteristic,parameter, or value need not be achieved exactly, but that deviations orvariations, including for example, tolerances, measurement error,measurement accuracy limitations and other factors known to those ofskill in the art, may occur in amounts that do not preclude the effectthe characteristic was intended to provide.

It is known to those skilled in the art that blocks of a flowchart (orsequence diagram) and a combination of flowcharts may be represented andexecuted by computer program instructions. These computer programinstructions may be loaded on a processor of a general purpose computer,special purpose computer, or programmable data processing equipment.When the loaded program instructions are executed by the processor, theycreate a means for carrying out functions described in the flowchart.Because the computer program instructions may be stored in a computerreadable memory that is usable in a specialized computer or aprogrammable data processing equipment, it is also possible to createarticles of manufacture that carry out functions described in theflowchart. Because the computer program instructions may be loaded on acomputer or a programmable data processing equipment, when executed asprocesses, they may carry out operations of functions described in theflowchart.

A block of a flowchart may correspond to a module, a segment, or a codecontaining one or more executable instructions implementing one or morelogical functions, or may correspond to a part thereof. In some cases,functions described by blocks may be executed in an order different fromthe listed order. For example, two blocks listed in sequence may beexecuted at the same time or executed in reverse order.

In this description, the words “unit,” “module” or the like may refer toa software component or hardware component, such as, for example, afield-programmable gate array (FPGA) or an application-specificintegrated circuit (ASIC) capable of carrying out a function or anoperation. However, a “unit,” or the like, is not limited to hardware orsoftware. A unit, or the like, may be configured so as to reside in anaddressable storage medium or to drive one or more processors. Units, orthe like, may refer to software components, object-oriented softwarecomponents, class components, task components, processes, functions,attributes, procedures, subroutines, program code segments, drivers,firmware, microcode, circuits, data, databases, data structures, tables,arrays or variables. A function provided by a component and unit may bea combination of smaller components and units, and may be combined withothers to compose larger components and units. Components and units maybe configured to drive a device or one or more processors in a securemultimedia card.

Prior to the detailed description, terms or definitions necessary tounderstand the disclosure are described. However, these terms should beconstrued in a non-limiting way.

The “base station (BS)” is an entity communicating with a user equipment(UE) and may be referred to as BS, base transceiver station (BTS), nodeB (NB), evolved NB (eNB), access point (AP), fifth generation (5G) NB(5GNB), or next generation NB (gNB).

The “UE” is an entity communicating with a BS and may be referred to asUE, device, mobile station (MS), mobile equipment (ME), or terminal.

In the fifth generation (5G) wireless communication system (alsoreferred as next generation radio or NR), system information (SI) (i.e.,one or more system information blocks (SIBs) or SI messages) istransmitted over a physical downlink shared channel (PDSCH). The carrierbandwidth (BW) is also partitioned into multiple bandwidth parts (BWPs)in frequency domain. The PDSCH carrying SI is transmitted over theinitial downlink (DL) BWP. The configuration of initial DL BWP issignaled in a master information block (MIB). The MIB contents and layer1 (L1) contents together are transmitted as one transport block alongwith a 24 bit cyclic redundancy check (CRC) on a physical broadcastchannel (PBCH. The PBCH is transmitted in a synchronization signal (SS)block (SSB) together with synchronization signals (i.e., primary SS(PSS)/secondary SS (SSS)). The SSB spans 4 orthogonal frequency divisionmultiplex (OFDM) symbols in time domain and 240 subcarriers in frequencydomain. The subcarrier spacing (SCS) used for SSB is fixed per frequencyband. There is a configurable offset between starting resource block(RB) of SSB and starting RB of initial DL BWP. The SCS used for SSBcarrying MIB and SCS for other DL channels (physical downlink controlchannel (PDCCH)/PDSCH used for system information) transmitted ininitial DL BWP can also be different.

In the legacy system, whenever a UE receives a paging message includingan SI update notification, the UE always reacquire the MIB irrespectiveof whether the MIB is updated or not. In next generation radio, MIBcontains several parameters, such as systemFrameNumber (6 bits mostsignificant bit (MSB)), subCarrierSpacingCommon, ssb-SubcarrierOffset,dmrs-TypeA-Position, pdcch-ConfigSIB1, cellBarred andintraFreqReselection information. Once the UE has acquiredsystemFrameNumber in a cell, the UE does not need to reacquire MIB againfor systemFrameNumber while staying on the camped cell in IDLE/INACTIVEstate or while being served in CONNECTED state. However, if the UEundergoes cell re-selection in IDLE/INACTIVE state or handover inCONNECTED state, the UE needs to reacquire MIB of re-selected/targetcell. The parameters ssb-SubcarrierOffset, dmrs-TypeA-Position,pdcch-ConfigSIB1, cellBarred, and intraFreqReselection can be updated bynetwork in a cell but these updates happen rarely. MIB contents aretransmitted on PBCH along with L1 contents comprising systemFrameNumber(4 bits least significant bit (LSB)), half frame bit and 3 bits forSS/PBCH block index (3 MSBs for above 6 GHz operation), otherwise, 1 bitfor subcarrier (SC) offset and 2 bits reserved (for below 6 GHzoperation). The total PBCH size including MIB contents, L1 contents and24 bits CRC is 56 bits. Also these parameters (i.e., MIB contents and L1contents) are not updated whenever one or more SIBs are updated bynetwork. Therefore, reacquiring MIB every time one or more SIBs areupdated is unnecessary.

In next generation radio, acquisition of MIB may require UE to switch toBW of SSB from BW of initial DL BWP (where UE receives remaining minimumsystem information (RMSI)/on demand SI (OSI)/Paging), as there is aconfigurable offset between starting RB of SSB and starting RB ofinitial DL BWP. Acquisition of MIB may also require SCS switching as SCSused for MIB and SCS for other DL channels (PDCCH/PDSCH used forRMSI/OSI/Paging) can be different. The RRC CONNECTED UE, UE can beconfigured to monitor and receive DL transmissions from gNB in one ormore DL BWPs. DL BWPs in which UE receive in DL is referred as active DLBWP. The acquisition of MIB every time any SI is updated leads to datainterruption for RRC CONNECTED UE as MIB may not be present in UE'sactive DL BWP. The acquisition of MIB every time any SI is updated leadsto data interruption, unnecessary power consumption and delay to acquireto the updated system information.

Method 1:

In order to overcome the abovementioned issues, in one method of thedisclosure, upon receiving SI update notification from gNB, UEreacquires MIB (i.e., decode PBCH) only if one or more MIB parameters(other than systemFrameNumber) are updated. The SI update notificationcan be received in paging message. Alternately SI update notificationcan be received in paging downlink control information (DCI) wherein thePDCCH is addressed to paging radio network temporary identifier(P-RNTI).

Embodiment 1: MIB Update Indication or PBCH Update Indication in PagingMessage or Paging DCI

In order to enable the UE to determine whether parameters of MIBcontents or L1 contents are updated or whether UE should reacquire MIB,gNB may transmit a notification (e.g., ‘MIBUpdateIndication,’‘MIBUpdateNotification,’ MIBReacquireNotification,’‘MIBReacquireIndication,’ or ‘PBCHUpdateIndication’). This notificationcan be transmitted in a paging message. Alternately this notificationcan be transmitted in DCI wherein the PDCCH is addressed to P-RNTI.

In an embodiment, this notification can be a one bit notificationindicating TRUE (1) or FALSE (0) wherein upon receiving thisnotification, the UE reacquires MIB, i.e., decodes PBCH if notificationis set to TRUE and UE does not reacquire MIB, i.e., no need to decodePBCH if notification is set to FALSE. The network (i.e., gNB) sets thisnotification to TRUE if it wants to update the parameter(s) of the MIBcontents and/or L1 contents of PBCH other than systemFrameNumber.Otherwise it sets the notification to FALSE.

In another embodiment, this notification can be optionally included inpaging message or paging DCI wherein the notification is set to TRUE ifit is included. Upon receiving this notification, the UE reacquire MIB,i.e., decodes PBCH if notification set to TRUE is included in pagingmessage or paging DCI. The network (i.e., gNB) includes thisnotification in a paging message or paging DCI if it wants to update theparameter (s) of the MIB contents or L1 contents of PBCH other thansystemFrameNumber.

FIG. 1 shows UE operations based on Embodiment 1 according to Method 1of the disclosure.

Referring to FIG. 1 , the UE receives a paging message or a paging DCI,at operation 110. The UE determines whether the received paging messageor the paging DCI includes an MIB update indication or a PBCH updateindication, at operation 120. If the received paging message or thepaging DCI includes the MIB update indication or the PBCH updateindication, the UE may reacquire the MIB, i.e., decode PBCH, atoperation 130. If the received paging message or the paging DCI does notinclude the MIB update indication or the PBCH update indication, the UEdoes not reacquire the MIB, i.e., do not decode PBCH, at operation 140.

FIG. 2 shows signaling between a UE and a gNB wherein the notificationis included in paging message based on Embodiment 1 according to Method1 of the disclosure.

Referring to FIG. 2 , the gNB determines whether to update one or moreparameters of MIB contents or L1 contents, at operation 210. If the gNBwants to update one or more parameters of MIB contents or L1 contents,the gNB transmits control information through PDCCH addressed to P-RNTI,at operation 220, and the gNB transmits a paging message including anMIB update indication or a PBCH update indication though PDSCH, atoperation 230. The UE reacquires the MIB, i.e., decodes PBCH, atoperation 240.

FIG. 3 shows signaling between a UE and a gNB wherein the notificationis included in paging DCI based on Embodiment 1 according to Method 1 ofthe disclosure.

Referring to FIG. 3 , the gNB determines whether to update one or moreparameters of MIB contents or L1 contents, at operation 310. If the gNBwants to update one or more parameters of MIB contents or L1 contents,the gNB transmits control information through PDCCH addressed to P-RNTI,at operation 320. The control information includes an MIB updateindication or a PBCH update indication. The UE reacquires the MIB, i.e.,decodes PBCH, at operation 330.

It is to be noted that P-RNTI used in FIG. 2 and FIG. 3 can be the sameor different.

It is to be noted that, in a system in which MIB update notification isincluded only in paging DCI, a UE checks for this notification in pagingDCI and not in paging message.

Embodiment 2: MIB Update Indication or PBCH Update Indication UsingP-RNTI

In an embodiment, the MIB update notification or PBCH updatenotification can be indicated in paging message or paging DCI by using aP-RNTI reserved for indicating MIB update/PBCH update. In this case, MIBupdate notification bit is not needed in paging message or paging DCI.The PDCCH will be addressed (i.e., CRC is masked) to this reservedP-RNTI if the network (i.e., gNB) wants the UE to reacquire the MIB(i.e., decode PBCH). Otherwise the network will use the other P-RNTI.

FIG. 4 shows UE operations based on Embodiment 2 according to Method 1of the disclosure.

FIG. 4 illustrates an SI response reception according to Embodiment 1Aof the disclosure.

Referring to FIG. 4 , the UE receives a paging message or a paging DCI,at operation 410. The UE determines whether the received paging messageor the paging DCI is addressed to P-RNTI reserved for an MIB updateindication or a PBCH update indication, at operation 420. If thereceived paging message or the paging DCI is addressed to P-RNTIreserved for the MIB update indication or the PBCH update indication,the UE may reacquire the MIB, i.e., decode PBCH, at operation 430. Ifthe received paging message or the paging DCI is not addressed to P-RNTIreserved for the MIB update indication or the PBCH update indication,the UE does not reacquire the MIB, i.e., does not decode PBCH, atoperation 440.

Embodiment 3: MIB Update Indication/PBCH Update Indication+UpdateIndication for SIB 1

FIG. 5 shows UE operations for an MIB and SI update based on Embodiment3 according to Method 1 of the disclosure.

Referring to FIG. 5 , upon receiving the paging message or paging DCI,at operation 510, UE checks whether MIB update notification (or PBCHupdate indication) is included in the received paging message or pagingDCI or not, at operation 520. If yes, UE reacquires the MIB (i.e.,decodes PBCH), at operation 530. Otherwise, UE does not reacquire theMIB (i.e., does not decode PBCH), at operation 540.

In an embodiment, the MIB update notification or PBCH updatenotification can be indicated in paging message or paging DCI by using aP-RNTI reserved for indicating MIB update. In this case MIB updatenotification bit is not needed in paging message or paging DCI. ThePDCCH will be addressed (i.e., CRC is masked) to this reserved P-RNTI ifthe network wants the UE to reacquire the MIB (i.e. decode PBCH).Otherwise network will use the other P-RNTI. In this embodiment, UE willcheck whether the received paging message or paging DCI is addressed toP-RNTI reserved for MIB update indication or not. If yes, UE reacquiresthe MIB. Otherwise UE does not reacquire the MIB.

UE also checks whether SIB1 or SI update notification is included inreceived paging message or paging DCI or not, at operation 550. If yes,UE reacquires the SIB1, at operation 560. Otherwise UE does notreacquire SIB1, at operation 570. Upon reacquiring SIB1, for each SIB(other than SIBs related to emergency notifications) which UE needs tomaintain depending on its state and/or service supported by it, UEreacquires that SIB if valueTag of that SIB in reacquired SIB1 ischanged and UE does not have a valid stored SI corresponding to the newvalueTag for that SIB, at operation 580. For SIBs related to emergencynotifications (i.e., earthquake and tsunami warning system(ETWS)/commercial mobile alert system (CMAS)), paging message or pagingDCI can include separate notification(s) indicating UE to reacquirethese earthquake and tsunami warning system (ETWS)/commercial mobilealert system (CMAS) SIB(s).

The SIB1Updationindication is included in paging message or paging DCIwhen network (NW) wants to update for, e.g., the contents of SIB1, i.e.,camping parameters, scheduling information, (excluding the toggling ofon-demand indicator) or if camping parameters, scheduling information,etc. does not change but individual valuetag of any SIB (other thanETWS/CMAS) in SIB1 changes.

FIG. 6 shows signaling between a UE and a gNB based on Embodiment 3according to Method 1 of the disclosure.

Referring to FIG. 6 , the gNB determines whether to update one or moreparameters of MIB contents and/or SIB1 contents, at operation 610. Ifthe gNB wants to update one or more parameters of MIB contents and/orSIB1 contents, the gNB transmits paging message or paging DCI, atoperation 620. The paging message or paging DCI includes an MIB updateindication and/or an SIB1 update indication. If the MIB updateindication is included in the paging message or paging DCI, the UEreacquires the MIB (i.e., decodes PBCH), at operation 630. If the SIB1update indication is included in the paging message or paging DCI, theUE reacquires the SIB1, at operation 640.

It is to be noted that, in a system in which an MIB update notificationand an SIB1 update notification are included only in paging DCI, a UEchecks for these notifications in paging DCI and not in paging message.

Embodiment 4: MIB Update Indication/PBCH Update Indication+UpdateIndication for Each SIB

In this embodiment, UE reacquires MIB (if updated) and only updated SIBaccording to indication.

FIG. 7 shows UE operations for an MIB and SI update based on Embodiment3 according to Method 1 of the disclosure. In this embodiment, updateindication is there for each individual SIB in paging message/pagingDCI. The update indication is also there for MIB in pagingmessage/paging DCI. In this embodiment, update indication can be therefor each individual SI message in paging message/paging DCI. Each SImessage carries one or more SIBs wherein the mapping between SI messagesand SIBs is signaled in SIB 1.

Referring to FIG. 7 , upon receiving the paging message or paging DCI,at operation 710, UE checks whether MIB update notification/PBCH Updatenotification is included in the received paging message or paging DCI ornot, at operation 720. If yes, the UE reacquires the MIB (i.e., decodesPBCH), at operation 730. Otherwise, the UE does not reacquire the MIB(i.e., does not decode PBCH), at operation 740.

In an embodiment, the MIB update notification/PBCH update notificationcan be indicated in paging message or paging DCI by using a P-RNTIreserved for indicating MIB update/PBCH update. In this case MIB updatenotification bit is not needed in paging message or paging DCI. ThePDCCH will be addressed (i.e., CRC is masked) to this reserved P-RNTI ifnetwork wants UE to update the MIB. Otherwise, network will use theother P-RNTI. In this embodiment, UE will check whether the receivedpaging message or paging DCI is addressed to P-RNTI reserved for MIBupdate indication or not. If yes, UE reacquires the MIB. Otherwise UEdoes not reacquire the MIB.

For each SIB which UE needs to maintain depending on its state and/orservice supported by it, UE also checks whether an update notificationis included in received paging message or paging DCI or not for thatSIB, at operation 750. If yes, UE reacquires that SIB if UE does nothave a valid stored SI corresponding to the new valueTag for that SIB,at operation 760. In an embodiment, UE can read the SIB1 in order todetermine the new valueTag of that SIB by reading SIB 1. Alternately, UEcan obtain the new valueTag of that SIB from the received paging messageor paging DCI. In yet another embodiment, the new valuetag correspondingto the updated SIB is included in the SIB itself and UE reacquires theupdated SIB contents along with the new valuetag. In this case, sincenew valuetag of updated SIB is not included in paging message/paging DCIand UE does not reacquire SIB1 for new valuetag, the UE cannot determineif the stored valid SI corresponds to new valuetag of updated SIB.Therefore, the UE needs to reacquire the updated SIB. If the receivedpaging message or paging DCI does not include the update notification(i.e., SIB X UpdateIndication), the UE does not reacquire that SIB(i.e., SIB X), at operation 770.

It is to be noted that, in a system in which update notification(s) areincluded only in paging DCI, a UE checks for these notifications inpaging DCI and not in paging message.

For indicating update indication for each SIB, following design optionsare proposed.

1) Paging message or paging DCI includes one bit indication for eachSIB. Each of these can be set to TRUE (1) or FALSE (0).

2) Paging message or paging DCI includes one bit indication for eachSIB. Each of these is optionally included. If included the value ofindication is TRUE.

3) Paging message or paging DCI includes a variable size bit string.Each bit in the bit string corresponds to an SIB/SI message. The lengthof bit string is also included in paging message or paging DCI. The MIBupdate indication is a separate bit than the variable size bit string.

4) Paging message or paging DCI includes a list of bit strings (eachstring 8 bits). For example, each bit in bit string 1 in the listcorresponds to SIB 1 to SIB 8. Each bit in bit string 2 in the listcorresponds to SIB 9 to SIB 16. And so on. The MIB update indication isa separate bit than the list of bit strings.

5) Paging message or paging DCI includes multiple bit strings orbitmaps. Each of these bit strings is optionally included.

-   -   SIB bit map 1 (for SIB1-8)    -   SIB bit map 2 (for SIB9-16)    -   SIB bit map 3 (for SIB17-24)

Each bit map is optional. The MIB update indication is a separate bitthan the list of bitmaps.

Paging message or paging DCI includes a list of one or more SI-indicescorresponding to SI messages which are updated. SI message correspondingto first entry in schedulingInfoList has SI-index zero, SI messagecorresponding to second entry in schedulingInfoList has SI-index one, SImessage corresponding to nth entry in schedulingInfoList has SI-indexn−1. schedulingInfoList is signaled by gNB in SIB1. For each SIB whichUE needs to maintain depending on its state and/or service supported byit, it checks whether the SI-index of SI message to which that SIB ismapped is included in paging message or paging DCI or not. If yes, UEreacquires that SIB if UE does not have a valid stored SI correspondingto the new valueTag for that SIB. In an embodiment, UE can read the SIB1in order to determine the new valueTag of that SIB by reading SIB 1.Alternately, UE can obtain the new valueTag of that SIB from thereceived paging message or paging DCI.

In an embodiment, gNB transmits SI update notification in paging messageor paging DCI. Here, the gNB transmits this for updating any SI (otherthan emergency SIBs). In this embodiment, acquisition of MIB uponreceiving the SI Update Notification is performed by UE in RRCIDLE/INACTIVE state. UE in RRC CONNECTED receives the updated parameters(such as SCS of initial DL BWP, dmrs-TypeA-Position, pdcch-ConfigSIB1)of MIB in dedicated RRC signaling message from gNB. There is no need forRRC CONNECTED state UEs to decode PBCH to reacquire updated MIB contentsor updated L1 encoding upon receiving SI update notification. Uponreceiving SI update notification UE in RRC CONNECTED as well as UE inRRC IDLE/INACTIVE reacquires SIB 1. In embodiments whereMIBUpdateNotification is transmitted by gNB in paging message or pagingDCI, upon receiving MIBUpdateNotification, acquisition of MIB isperformed by UE in RRC IDLE/INACTIVE state. RRC CONNECTED UE does notacquire MIB upon receiving MIBUpdateNotification.

MIB Update Considering BWPs

Method 2:

FIG. 8 illustrates gNB operations in one embodiment according to Method2 of the disclosure.

Referring to FIG. 8 , if gNB wants to update one or more parameters forMIB, at operation 810, it transmits paging message or paging DCIincluding MIBUpdateIndication, wherein the paging message is transmittedon initial DL BWP, at operation 820. Further, the gNB also transmitsdedicated RRC message including updated parameters of MIB contentsand/or updated L1 contents of PBCH transport block to the RRC CONNECTEDUE(s) whose current active DL BWP is not the initial DL BWP, atoperation 830. In this method, RRC CONNECTED UE(s) whose current activeDL BWP is not initial DL BWP, receives the updated parameters (such asSCS of initial DL BWP, dmrs-TypeA-Position, pdcch-ConfigSIB1) of MIBcontents and/or updated L1 contents of PBCH which are needed in RRCCONNECTED state in dedicated RRC message (e.g., inRRCReconfigurationMessage). The MIB contents and/or updated L1 contentsof PBCH which are needed in RRC CONNECTED state may includesubCarrierSpacingCommon, dmrs-TypeA-Position, and pdcch-ConfigSIB1(i.e., search space zero and control resource set (CORESET) zero).

Method 3:

FIG. 9 illustrates gNB operations in one embodiment according to Method3 of the disclosure.

Referring to FIG. 9 , if gNB wants to update one or more parameters forMIB contents and/or L1 contents of PBCH, at operation 910, it transmitspaging message or paging DCI includingMIBUpdateIndication/PBCHUpdateIndication, wherein the paging message istransmitted on initial DL BWP, at operation 920. Further, the gNB alsotransmits dedicated RRC message (e.g. in RRCReconfigurationMessage)including updated parameters of MIB contents and/or L1 contents of PBCHto all the RRC CONNECTED UE(s), at operation 930. In this method, RRCCONNECTED UE(s) receives the updated parameters of MIB contents and/orupdated L1 contents of PBCH in dedicated RRC message. Here, an RRCCONNECTED UE does not need decode PBCH to acquire MIB to receive theupdated parameters (such as SCS of initial DL BWP, dmrs-TypeA-Position,pdcch-ConfigSIB1) of MIB (even if it receives paging message indicatingMIB update). The MIB contents and/or updated L1 contents of PBCH whichare needed in RRC CONNECTED state may include subCarrierSpacingCommon,dmrs-TypeA-Position, and pdcch-ConfigSIB1 (i.e., search space zero andCORESET zero).

Method 4:

FIG. 10 illustrates gNB operations in one embodiment according to Method3 of the disclosure.

Referring to FIG. 10 , if gNB wants to update one or more parameters forMIB contents and/or update L1 contents of PBCH, at operation 1010, ittransmits paging message or paging DCI includingMIBUpdateIndication/PBCHUpdateIndication, wherein the paging message istransmitted on initial DL BWP, at operation 1020. Further, the gNB alsotransmits dedicated RRC message (e.g. in RRCReconfigurationMessage)including updated parameters (such as SCS of initial DL BWP,dmrs-TypeA-Position, pdcch-ConfigSIB1) of MIB contents and/or updated L1contents of PBCH to the RRC CONNECTED UE(s) whose current active DL BWPis not the initial DL BWP, at operation 1030. If the active DL BWP ofRRC CONNECTED UE is initial DL BWP and UE does not have the capabilityto receive both MIB and unicast data simultaneously, the gNB transmitsdedicated RRC message (e.g. in RRCReconfigurationMessage) includingupdated parameters of MIB contents and/or updated L1 contents of PBCH tothis RRC Connected UE, at operation 1040. The capability to receive bothMIB (i.e., decode PBCH) and unicast data (i.e., decode PDSCH)simultaneously is indicated to gNB by UE in UE capability message. Inthis method, if the active DL BWP of RRC CONNECTED UE is initial DL BWPand UE does not have the capability to receive both MIB and unicast datasimultaneously, the UE will not decode PBCH to read MIB (even if itreceives paging message indicating MIB update). It will receive theupdated MIB contents and/or updated L1 contents of PBCH in dedicated RRCmessage from gNB. The MIB contents and/or updated L1 contents of PBCHwhich are needed in RRC CONNECTED state may includesubCarrierSpacingCommon, dmrs-TypeA-Position, and pdcch-ConfigSIB1(i.e., search space zero and CORESET zero).

Method 5:

FIG. 11 illustrates gNB operations in one embodiment according to Method3 of the disclosure.

Referring to FIG. 11 , if gNB wants to update one or more parameters forMIB contents and/or update L1 contents of PBCH, at operation 1110, ittransmits paging message or paging DCI includingMIBUpdateIndication/PBCHUpdateIndication, wherein the paging message istransmitted on initial DL BWP, at operation 1120. Further, the gNB alsotransmits dedicated RRC message (e.g. in RRCReconfigurationMessage)including updated parameters (such as SCS of initial DL BWP,dmrs-TypeA-Position, pdcch-ConfigSIB1) of MIB contents and/or updated L1contents of PBCH to the RRC CONNECTED UE(s) whose current active DL BWPis not the initial DL BWP, at operation 1130. If the active DL BWP ofRRC CONNECTED UE is initial DL BWP and SCS of MIB/PBCH is different thanthe SCS of initial DL BWP or BWP of MIB/PBCH is not within the BWmonitored by UE for PDCCH, the gNB transmits dedicated RRC message (e.g.in RRCReconfigurationMessage) including updated parameters (such as SCSof initial DL BWP, dmrs-TypeA-Position, pdcch-ConfigSIB1) of MIBcontents and/or updated L1 contents of PBCH to this RRC Connected UE, atoperation 1140. In this method, if the active DL BWP of RRC CONNECTED UEis initial DL BWP and SCS of MIB/PBCH is different than the SCS ofinitial DL BWP or BWP of MIB/PBCH is not within the BW monitored by UEfor PDCCH, the UE will not decode PBCH to read MIB (even if it receivespaging message indicating MIB update). It will receive the updated MIBcontents and/or updated L1 contents of PBCH in dedicated RRC messagefrom gNB. The MIB contents and/or updated L1 contents of PBCH which areneeded in RRC CONNECTED state may include subCarrierSpacingCommon,dmrs-TypeA-Position, and pdcch-ConfigSIB1 (i.e., search space zero andCORESET zero).

Method 6:

FIG. 12 illustrates gNB operations in one embodiment according to Method3 of the disclosure.

Referring to FIG. 12 , if gNB wants to update one or more parameters forMIB contents and/or update L1 contents of PBCH, at operation 1210, gNBswitches the RRC Connected UE(s) whose current active DL BWP is not theinitial DL BWP to initial DL BWP, at operation 1220. It then transmitspaging message or paging DCI includingMIBUpdateIndication/PBCHUpdateIndication, wherein the paging message orpaging DCI is transmitted on initial DL BWP, at operation 1230.

Method 7:

FIG. 13 illustrates gNB operations in one embodiment according to Method3 of the disclosure.

Referring to FIG. 13 , if gNB wants to update one or more parameters forMIB contents and/or update L1 contents of PBCH, at operation 1310, gNBswitches the RRC Connected UE(s) whose current active DL BWP is not theinitial DL BWP and who has the capability to receive both MIB (i.e.,decode PBCH) and unicast data (i.e., decode PDSCH) simultaneously toinitial DL BWP, at operation 1320. It then transmits paging message orpaging DCI including MIBUpdateIndication/PBCHUpdateIndication, whereinthe paging message is transmitted on initial DL BWP, at operation 1330.The capability to receive both MIB (i.e., decode PBCH) and unicast data(i.e., decode PDSCH) simultaneously is indicated to gNB by UE in UEcapability message. If the UE does not have the capability to receiveboth MIB and unicast data simultaneously, gNB transmits dedicated RRCmessage (e.g. in RRCReconfigurationMessage) including updated parameters(such as SCS of initial DL BWP, dmrs-TypeA-Position, pdcch-ConfigSIB1)of MIB contents and/or updated L1 contents of PBCH to this RRC connectedUE, at operation 1340. In this method, if the active DL BWP of RRCCONNECTED UE is initial DL BWP and UE does not have the capability toreceive both MIB and unicast data simultaneously, the UE will not decodePBCH to read MIB (even if it receives paging message indicating MIBupdate). It will receive the updated MIB contents and/or updated L1contents of PBCH in dedicated RRC message (e.g. inRRCReconfigurationMessage) from gNB. The MIB contents and/or updated L1contents of PBCH which are needed in RRC CONNECTED state may includesubCarrierSpacingCommon, dmrs-TypeA-Position, and pdcch-ConfigSIB1(i.e., search space zero and CORESET zero).

Access Control Enabled/Disabled Indication

The access control parameters are signaled in a separate SIB. Accesscontrol is cell-specific and a radio access network (RAN) (i.e., gNB)decides to apply access control to mitigate an RAN overload situation.When the cell is not loaded, there is no reason to apply access control.When load is high, access control is enabled and UE is required toacquire access control SIB in order to apply barring parameters. Theissue is how the UE knows whether the access control is enabled ordisabled.

Idle/Inactive UEs are required to monitor paging every paging occasion.Therefore, in one method of the disclosure, an access control bit isincluded in paging message/DCI. Upon receiving the paging message, ifthe access control bit is set to TRUE (1), UE will enable accesscontrol. Otherwise, it will consider the access control as disabled. Ifthe access control bit is set to TRUE (1), to enable access control,i.e., to apply barring parameters, the UE is required to acquire theaccess control SIB.

Alternately, whether access control is enabled/disabled can be indicatedin SIB 1. It could be one access control enabled bit in SIB 1.Alternately, presence/absence of access control parameters in SIB1 canindicate whether access control is enabled/disabled. Alternately,presence/absence of scheduling information of access control SIB orpresence/absence of access control SIB in list of SIBstransmitted/supported in SIB1 can indicate whether access control isenabled/disabled. If the access control bit is set to TRUE (1) in SIB1,to enable access control, i.e., to apply barring parameters, the UE isrequired to acquire the access control SIB according to the schedulinginformation of access control SIB. If the access control bit is set toFALSE (0) in SIB1, i.e., access control is disabled, then UE is notrequired to acquire the access control SIB.

Alternately, if scheduling information of access control SIB is presentor access control SIB is present in list of SIBs available in cell, thenimplicitly UE determines access control is enabled, in order to applybarring parameters the UE is required to acquire the access control SIBaccording to the scheduling information of access control SIB.

Access control is enabled/disabled can be indicated in MIB. It could beone access control enabled bit in MIB. If the access control bit is setto TRUE (1) in MIB, to enable access control, i.e., to apply barringparameters, the UE is required to acquire SIB 1. The access control SIBis acquired based on the scheduling information of access control SIB inthe acquired SIB 1. If the access control bit is set to FALSE (0) inMIB, i.e., access control is disabled, then UE is not required toacquire the access control SIB.

If the access control enabling/disabling bit is included in MIB, and ifthis bit toggles, then it is considered as MIB content update. In thiscase, the network will indicate theMIBUpdateIndication/PBCHUpdateIndication through paging message and/orpaging DCI. The UE is required to reacquire MIB contents and determinewhether to enable/disable access control based on the updated indicationin MIB.

If the access control enabling/disabling bit is included in SIB 1, andif this bit toggles, then it is considered as SIB1 content update. Inthis case the network will indicate the SIB 1UpdateIndication throughpaging message and/or paging DCI. The UE is required to reacquire SIB1contents and determine whether to enable/disable access control based onthe updated indication in SIB 1.

Further, if the SIB X Update indication in the paging message or pagingDCI indicates update of access control SIB, then the UE acquires theupdated access control SIB in the current modification period instead ofwaiting for the next modification period boundary.

In an embodiment, if the access control bit is enabled in MIB or SIB1,UE is not required to send SI request but UE acquires access control SIBfrom broadcast. If access control bit is enabled and UE does not havestored SI, then UE acquires access control SIB from broadcast and doesnot trigger SI request.

Paging Occasion (PO) Calculation

In the wireless communication system, the paging is transmitted to pageUE(s) which are attached to the wireless communication network but arein RRC idle/inactive mode. In the RRC idle/inactive mode, a UE wake upsat regular intervals (i.e., every paging DRX cycle) for short periods toreceive paging, to receive SI update notification, and to receiveemergency notifications. Paging message is transmitted using PDSCH.PDCCH is addressed to P-RNTI if there is a paging message in PDSCH.P-RNTI is common for all UEs. UE identity (e.g., system architectureevolution (SAE)-temporary mobile subscriber identity (S-TMSI)) isincluded in paging message to indicate paging for a specific UE. Pagingmessage may include multiple UE identities to page multiple UEs. Pagingmessage is broadcasted (i.e., PDCCH is masked with P-RNTI) over datachannel (i.e., PDSCH). SI update and emergency notifications areincluded in DCI and PDCCH carrying this DCI is addressed to P-RNTI. Inthe RRC idle/inactive mode, UE monitors one paging occasion (PO) everyDRX cycle. In RRC connected state, UE monitors one or more POs toreceive SI update notification and to receive emergency notifications.UE can monitor any PO in paging DRX cycle and monitors at least one POin SI modification period.

In the legacy system, one PO is a subframe/transmission time interval(TTI) of 1 ms duration. Network may configure several POs in a DRXcycle. UE determines its PO based on UE ID. UE first determines thepaging frame (PF) and then determine the PO within the PF. One PF is aradio frame (10 ms), which may contain one or multiple POs. Every radioframe in a DRX cycle can be a paging frame. There can be up to four POsin a PF. The subframes which can be PO in a PF are pre-defined, i.e.,subframe #0, subframe #4, subframe #5, and subframe #9. The networksignals two parameters. The first parameter is ‘T,’ i.e., paging DRXcycle duration in number of radio frames. The second parameter is ‘nB,’i.e., number of POs in a paging DRX cycle. Here, nB can be configured toone value among 4T, 2T, T, T/2, T/4, T/8, T/16, and T/32. UEs aredistributed across several POs in the DRX cycle based on UE ID. SeveralUEs can be mapped to same PO. The PF for a UE is the radio frame withsystem frame number ‘SFN’ which satisfies the equation SFN mod T=(T divN)*(UE_ID mod N); where N equal to min (T, nB) is the number of pagingframes in DRX cycle and UE_ID is equal to international mobilesubscriber identity (IMSI) mod 1024. Within the determined PF, the POcorresponds to i_s=floor(UE_ID/N) mod Ns; where Ns equal to max (1,nB/T) is the number of paging occasions in a paging frame; i_s can be 0,1, 2 and 3; mapping between i_s, Ns, and subframe within paging frame ispre-defined.

In the 5G wireless communication system operating in higher frequency(mm Wave) bands, UE and gNB communicates with each other usingbeamforming Beamforming techniques are used to mitigate the propagationpath losses and to increase the propagation distance for communicationat higher frequency band. Beamforming enhances the transmission andreception performance using a high-gain antenna. In general, thetransmission (TX) beamforming increases directivity by allowing an areain which propagation reaches to be densely located in a specificdirection by using a plurality of antennas. The use of the TXbeamforming results in the increase in the directivity of a signal,thereby increasing a propagation distance. Further, since the signal isalmost not transmitted in a direction other than a directivitydirection, a signal interference acting on another receiving end issignificantly decreased. By using beamforming technique, a transmittercan make plurality of transmit beam patterns of different directions.Each of these transmit beam patterns can be also referred as TX beam.Wireless communication system operating at high frequency uses pluralityof narrow TX beams to transmit signals in the cell as each narrow TXbeam provides coverage to a part of cell. The narrower the TX beam,higher is the antenna gain and hence the larger the propagation distanceof signal transmitted using beamforming In case of high frequency band,paging needs to be transmitted using beamforming. At higher frequencies,beamforming is essential to compensate for path loss. One TX beam cannotprovide the full cell coverage. Paging needs to be transmitted using themultiple TX beams. Since the number of TX beams depends on networkdeployment, the existing design wherein the duration of PO is onesubframe and locations of POs are pre-defined is inefficient and lacksscalability.

In the disclosure a scalable design is provided to determine PO. In thedisclosure, POs are determined in such a way that PDCCH monitoringoccasions for monitoring paging in PO are overlapping with PDCCHmonitoring occasions for RMSI (also known as SIB1). As a result,additional beam sweeping (if there are N TX beams at gNB, gNB transmitsusing these TX beams in N time intervals wherein each transmission isusing a different TX beam) for paging transmission can be avoided.

In a 5G wireless communication system, the synchronization signal andPBCH block (SSB) consists of primary and secondary synchronizationsignals (PSS, SSS) and PBCH in cell. An SSB burst set (comprising of aset of SSBs) is transmitted periodically where the periodicity is 5 ms,10 ms, 20 ms, 40 ms, 80 ms, and 160 ms.

FIG. 14 shows three patterns for transmitting RMSI in a 5G wirelesscommunication system.

Referring to FIG. 14 , “Pattern 1” refers to the multiplexing patternthat SS/PBCH block and RMSI CORESET occur in different time instances,and SS/PBCH block TX BW and BW containing RMSI CORESET overlap. “Pattern2” refers to the multiplexing pattern that SS/PBCH block and RMSICORESET occur in different time instances, and SS/PBCH block TX BW andthe BW containing RMSI CORESET do not overlap. “Pattern 3” refers to themultiplexing pattern that SS/PBCH block and RMSI CORESET occur in thesame time instance, and SS/PBCH block TX BW and the BW containing RMSICORESET do not overlap.

For pattern 1, a set of PDCCH monitoring occasions for RMSI occurs every20 ms starting from SFN 0. This set comprises PDCCH monitoring occasionfor each SSB. In this set, there is one to one mapping between PDCCHmonitoring occasion and SSB. The set of PDCCH monitoring occasions canbe located within a radio frame which satisfies SFN mod 2=0. The set ofPDCCH monitoring occasions can span multiple radio frames (i.e., PDCCHmonitoring occasions for some SSBs are in radio frame which satisfiesSFN mod 2=0 and PDCCH monitoring occasions for some SSBs are in radioframe which satisfies SFN mod 2=1. For pattern 2 or 3, a set of PDCCHmonitoring occasions for RMSI occurs every SS burst set period. Theradio frame is same as the radio frame in which SSB is transmitted. Thelocation of each PDCCH monitoring occasion for RMSI is determined asdefined in 3GPP TS 38.213.

Reference Radio Frame or Paging Frame for PO Determination

UE first derives the reference frame or paging frame. One paging frame(PF) is one radio frame and may contain one or multiple PO(s) orstarting point of a PO. Each radio frame in DRX cycle can be a pagingframe. In case the number of paging frames are less than number of radioframes in DRX cycle (i.e., each radio frame in DRX cycle is not a pagingframe), the legacy equation used in a 4G system always locates PO ineven radio frames. For RMSI pattern 3, the PO should be located in radioframe (odd or even) in which an SS burst set is transmitted. Forexample, if SS burst set period is 20 ms, network can transmit SS burstset in odd radio frames or in even radio frames. For pattern 1, offsetis 0 as PO always starts in radio frame for which SFN mod 2=0. Forpattern 2 or 3, offset is equal to smallest SFN in which SSBs aretransmitted. Therefore, in the disclosure the legacy equation isenhanced to include an offset. For paging procedures to be agnostic topatterns, offset may be signaled by the network. For example, the offsetis signaled in system information. In the disclosure, the PO monitoredby UE starts in radio frame which satisfies:(SFN+offset)mod T=(T div N)*(UE_ID mod N)

Where:

T: DRX cycle of the UE. T is determined by the shortest of the UEspecific DRX value, if allocated by upper layers (i.e. NAS), and adefault DRX value broadcast in system information. If UE specific DRX isnot configured by upper layers, the default value is applied. SFN is thesystem frame number or radio frame number;

N: number of paging frames in DRX cycle; and

UE_ID: IMSI mod 1024 or S-TMSI mode 1024.

PO Determination

In the disclosure, there can be one (Ns=1) or two (Ns=2) POs per pagingframe. In the disclosure, PDCCH monitoring occasions for paging is sameas the PDCCH monitoring occasions for RMSI (also known as SIB1). ThePDCCH monitoring occasions for RMSI are determined as specified inclause 13 of TS 38.213. PO is the set of PDCCH monitoring occasions forRMSI. This set includes PDCCH monitoring occasions for each SSB. FornB=2T (i.e., Ns=2), there are two POs within a radio frame, one in firsthalf frame of radio frame and another second half frame of radio frame.The UE monitors the PDCCH monitoring occasions for paging in the POpointed to by index i_s, where i_s is derived from the followingequation:i_s=floor(UE_ID/N)mod Ns.

Where:

Ns=number of paging occasions per paging frame.

TABLE Ns PO when i_s = 0 PO when i_s = 1 1 PO is the set of PDCCH N/Amonitoring occasions for RMSI, where the first PDCCH monitoring occasionfor RMSI starts in determined reference radio frame. 2 PO is the set ofPDCCH PO is the set of PDCCH monitoring occasions for monitoringoccasions for RMSI in 1^(st) half frame of RMSI in 2nd half framedetermined reference radio of determined reference frame. radio frame.

For Ns=1 and i_s=0, PO is the set of PDCCH monitoring occasions forRMSI, wherein the PO starts from the first PDCCH monitoring occasion orRMSI in determined reference frame (or paging frame).

For Ns=2 and i_s=0, PO is the set of PDCCH monitoring occasions for RMSIin 1^(st) half frame of determined reference frame (or paging frame);Note that each radio frame has two half frames.

For Ns=2 and i_s=1, PO is the set of PDCCH monitoring occasions for RMSIin 2nd half frame of determined reference frame (or paging frame); Notethat each radio frame has two half frames.

Multiple BWPs for Paging

In the existing system, all UEs camped to a cell monitors paging in theinitial DL BWP. The initial DL BWP is signaling in RMSI (or SIB1). Inorder to enhance the paging capacity, RMSI (or SIB1) can broadcast alist of DL BWPs for paging. Each of these DL BWPs is associated with aBWP ID. UE selects one of these DL BWPs for monitoring paging. Theselection can be done based on UE ID. A UE may monitor paging in DL BWPwith BWP ID ‘X’ where UE ID mod ‘number of DL BWPs’=X.

FIG. 15 is a block diagram of a terminal according to an embodiment ofthe disclosure.

Referring to FIG. 15 , a terminal includes a transceiver 1510, acontroller 1520, and a memory 1530. The controller 1520 may refer to acircuitry, an ASIC, or at least one processor. The transceiver 1510, thecontroller 1520, and the memory 1530 are configured to perform theoperations of the UE illustrated in the drawings, e.g., FIGS. 1 to 7 ,or described above. Although the transceiver 1510, the controller 1520,and the memory 1530 are shown as separate entities, they may be realizedas a single entity like a single chip. Alternatively, the transceiver1510, the controller 1520, and the memory 1530 may be electricallyconnected to or coupled with each other.

The transceiver 1510 may transmit and receive signals to and from othernetwork entities, e.g., a base station.

The controller 1520 may control the UE to perform functions according toone of the embodiments described above.

For example, the controller 1520 is configured to determine a PF basedon an offset used for PF determination ‘PF_offset,’ the DRX cycle of theterminal ‘T,’ the number of total PFs in the DRX cycle ‘N,’ and anidentifier of the terminal ‘UE_ID.’ The values of N and PF_offset arederived from the parameter in system information. The controller 1520 isconfigured to determine index ‘i_s’ indicating the index of PO in the PFbased on the identifier of the terminal ‘UE_ID,’ the number of PFs inthe DRX cycle ‘N,’ and the number of POs for the PF ‘Ns.’ The controller1520 is configured to determine a PO based on the number of POs for thePF ‘Ns,’ and the index of the PO in the PF ‘i_s.’ A PO is a set of PDCCHmonitoring occasions and can consist of multiple time slots (e.g.subframe or OFDM symbol) where paging DCI can be sent. One PF is oneradio frame and may contain one or multiple PO(s) or starting point of aPO. The PDCCH monitoring occasions for paging are same as for RMSI. Nsis either 1 or 2. For Ns=1, there is only one PO which starts from thefirst PDCCH monitoring occasion for paging in the PF. For Ns=2, PO iseither in the first half frame (i_s=0) or the second half frame (i_s=1)of the PF. The controller 1520 is configured to monitor the PO toreceive a paging message.

In another example, the controller 1520 is configured to control thetransceiver 1510 to receive an indication about change of systeminformation, and acquire a SIB1 based on a state of the terminal. Uponreceiving the SI update notification, the terminal in RRC IDLE/INACTIVEmay reacquire MIB whereas the RRC CONNECTED terminal may not reacquireMIB. In other words, the controller 1520 is configured to acquire a MIBif the terminal is in an RRC IDLE or INACTIVE state, whereas thecontroller 1520 is configured to skip acquisition of a MIB if theterminal is in an RRC_CONNECTED state. The indication may be received ina paging message or DCI to indicate the change of the systeminformation.

In an embodiment, the operations of the terminal may be implementedusing the memory 1530 storing corresponding program codes. Specifically,the terminal may be equipped with the memory 1530 to store program codesimplementing desired operations. To perform the desired operations, thecontroller 1520 may read and execute the program codes stored in thememory 1530 by using a processor or a central processing unit (CPU).

FIG. 16 is a block diagram of a base station according to an embodimentof the disclosure.

Referring to FIG. 16 , a base station (BS) includes a transceiver 1610,a controller 1620, and a memory 1630. The transceiver 1610, thecontroller 1620, and the memory 1630 are configured to perform theoperations of the network (e.g., gNB) illustrated in the drawings, e.g.,FIGS. 8 to 13 , or described above. Although the transceiver 1610, thecontroller 1620, and the memory 1630 are shown as separate entities,they may be realized as a single entity like a single chip. Thetransceiver 1610, the controller 1620, and the memory 1630 may beelectrically connected to or coupled with each other.

The transceiver 1610 may transmit and receive signals to and from othernetwork entities, e.g., a terminal. The controller 1620 may control theBS to perform functions according to one of the embodiments describedabove. The controller 1620 may refer to a circuitry, an ASIC, or atleast one processor. In an embodiment, the operations of the BS may beimplemented using the memory 1630 storing corresponding program codes.Specifically, the BS may be equipped with the memory 1630 to storeprogram codes implementing desired operations. To perform the desiredoperations, the controller 1620 may read and execute the program codesstored in the memory 1630 by using a processor or a CPU.

While the disclosure has been shown and described with reference tovarious embodiments thereof, it will be understood by those skilled inthe art that various changes in form and details may be made thereinwithout departing from the spirit and scope of the disclosure as definedby the appended claims and their equivalents.

What is claimed is:
 1. A method performed by a terminal in a wireless communication system, the method comprising: monitoring an indication on change of system information; identifying whether the indication on change of system information is received based on the monitoring; identifying radio resource control (RRC) states of the terminal; in case that the terminal is in an RRC idle state or an RRC inactive state, acquiring a system information block 1 (SIB1) after acquiring of a master information block (MIB); and in case that the terminal is in an RRC connected state and the indication is received, acquiring the SIB1.
 2. The method of claim 1, wherein the indication is received in a paging message.
 3. The method of claim 1, wherein the indication is received in downlink control information to indicate the change of the system information.
 4. A terminal in a wireless communication system, the terminal comprising: a transceiver; and a controller coupled with the transceiver and configured to: monitor an indication on change of system information, identify whether the indication on change of system information is received based on the monitoring, identify radio resource control (RRC) states of the terminal, in case that the terminal is in an RRC idle state or an RRC inactive state, acquire a system information block 1 (SIB1) after acquiring of a master information block (MIB), and in case that the terminal is in an RRC connected state and the indication is received, acquire the SIB1.
 5. The terminal of claim 4, wherein the controller is configured to: receive the indication in a paging message.
 6. The terminal of claim 4, wherein the controller is configured to: receive the indication in downlink control information to indicate the change of the system information.
 7. A method performed by a base station in a wireless communication system, the method comprising: identifying whether to transmit, to a terminal, an indication about change of system information; identifying radio resource control (RRC) states of the terminal; in case that the terminal is in an RRC idle state or an RRC inactive state, transmitting, to the terminal, a system information block 1 (SIB1) after transmitting of a master information block (MIB); and in case that the terminal is in an RRC connected state and the indication is transmitted to the terminal, transmitting, to the terminal, the SIB1.
 8. The method of claim 7, wherein the indication is transmitted in a paging message.
 9. The method of claim 7, wherein the indication is transmitted in downlink control information to indicate the change of the system information.
 10. A base station in a wireless communication system, the base station comprising: a transceiver; and a controller coupled with the transceiver and configured to: identify whether to transmit, to a terminal, an indication about change of system information, identify radio resource control (RRC) states of the terminal, in case that the terminal is in an RRC idle state or an RRC inactive state, transmit, to the terminal, a system information block 1 (SIB1) after transmitting of a master information block (MIB), and in case that the terminal is in an RRC connected state and the indication is transmitted to the terminal, transmit, to the terminal, the SIB1.
 11. The base station of claim 10, wherein the controller is configured to: transmit the indication in a paging message.
 12. The base station of claim 10, wherein the controller is configured to: transmit the indication in downlink control information to indicate the change of the system information. 